around. It would have been
easy enough to have used a
pre-built solution such as a
PlayStation or a normal RC
controller to drive the robot,
but I was concerned that
operating the robotic arm
would have proven difficult.
Plus, it wasn't as "clean" of a
system as I wanted it to be.
The picture that I had in
my head was for a person to
pick up the controller and
instantly know how to use it.
Thinking about it some more,
I realized that a person
wasn't driving a robot around
so much as they were
controlling a robotic arm.
This provided a solution for the configuration of the
I decided that I would build a miniature arm on the
controller whose movements would then be imitated by
the larger robotic arm. Further, holding down a button on
the controller would activate the drive system, then the
robot would move in the direction (forward/backward)
that the arm was pointed proportional to the amount the
arm was extended.
By combining the control of the robotic arm with its
movement, I allow the operator to concentrate on the
important thing: Getting the robot's gripper to the target
and affecting it.
With this controller, the operator didn't have to worry
about getting the robot too close or too far, they just had
to reach for it and the system did the rest. Best of all, the
design was simple and elegant. Just two things: the mini
arm and a button.
The mini arm is made up of the rotary potentiometers
(variable resistors) that are at each axis, whose positions
are determined by the microcontroller using a simple
capacitor/resistor decay circuit along with the Propeller
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